Switchable solar cell devices

ABSTRACT

Exemplary embodiments provide a solar cell device, and method for forming the solar cell device by integrating a switch component into a solar cell element. The solar cell element can include a solar cell, a solar cell array and/or a solar cell panel. The integrated solar cell element can be used for a solar sensor, while the solar sensor can also use discrete switches for each solar cell area of the sensor. Exemplary embodiments also provide a connection system for the solar cell elements and a method for super-connecting the solar cell elements to provide a desired connection path or a desired power output through switch settings. The disclosed connection systems and methods can allow for by-passing underperforming solar cell elements from a plurality of solar cell elements. In embodiments, the solar cell element can be extended to include a battery or a capacitor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.14/023,079, titled “SWITCHABLE SOLAR CELL DEVICES” and filed on Sep. 10,2013, which is a divisional of U.S. application Ser. No. 12/470,325,titled “SWITCHABLE SOLAR CELL DEVICES” and filed on May 21, 2009, whichclaims the benefit of and priority to U.S. Provisional Application No.61/147,888, titled “SOLAR CELL WITH INTEGRATED SWITCH AND CONNECTIONMETHOD”, and filed on Jan. 28, 2009, the disclosures of which areincorporated herein by reference.

FIELD OF THE INVENTION

This invention relates generally to solar cells and, more particularly,to devices and connection systems of solar cells, and methods forforming and arranging solar cells.

BACKGROUND OF THE INVENTION

Solar energy is a potentially large alternative energy source. The mostcommon form of solar cells is based on the photovoltaic (PV) effect inwhich light falling on a two-layer semiconductor device produces aphotovoltage or potential difference between the layers. Typically, suchcells are connected together in series in order to provide large workingvoltages. For example, an average panel usually includes 10 to 36full-sized solar cells connected in series, producing 6-20V and 10-100watts.

There are certain shortcomings, however, produced by the seriesconfigured solar cell panel. For example, the solar panel is verysensitive to the output of individual cells. Particularly, in the caseof a failure of any single solar cell in the series, the entire row ofsolar cells is lost due to this undesirable single-point failure. Inaddition, whenever sunlight is not cast evenly upon the solar cellpanel, such as when part of the solar cell panel is in the shade or ashadow, the solar cells receiving more light will produce a greatercurrent than the solar cells receiving less light. In that case, thecurrent output by each row of the cells will be limited to the lowestcurrent produced by any one solar cell in the row. This, in turn, causesa drop in output power for the solar cell panel. Further, such issuesmay become more important, as solar technology moves from commercialsettings into residential settings. This is because residential settingsfor solar cells will have limited sighting (or location) options andwill potentially suffer from poorer maintenance than in a commercialsetting.

Conventional methods to solve these failures include use of by-passdiodes. In this case, failed cells may be bypassed as the voltage dropacross the cells increases, but this is not a good solution when thereis more than one solar cell having lower output in the series of solarcells.

Thus, there is a need to overcome these and other problems of the priorart and to provide devices, and connection systems of solar cells andmethods for forming and arranging solar cells.

SUMMARY OF THE INVENTION

According to various embodiments, the present teachings include a devicethat includes a solar cell element. The solar cell element can includetwo solar cell terminals having a switch component integrated with atleast one of them. Such switch component can be used to control thesolar cell element and can include, for example, one or more MOS-basedswitches within the solar cell element. In various embodiments, thedevice that includes switchable solar cell element can be used for solarsensors.

According to various embodiments, the present teachings also include amethod for forming a solar device. The solar device can be formed from asemiconductor solar cell element that includes a p contact diffusionregion and an n contact diffusion region in a semiconductor substrate. AMOS-based structure can then be formed and integrated with at least oneof the n and p contact diffusion regions in the semiconductor substrate.In this manner, the MOS-based structure can be a switch to control thesemiconductor solar cell element.

According to various embodiments, the present teachings also include asolar sensor. The disclosed solar sensor can include a plurality ofsolar cell areas with each solar cell area having a solar pixel based ona diffusion length of a minority current carrier. The disclosed solarsensor can also include a plurality of switches with each switchindependently addressing one solar area. Electric output from each solarcell area that is controlled by a corresponding independent switch canbe read out and/or displayed.

According to various embodiments, the present teachings further includea sensing method using a solar sensor. In this method, a plurality ofsolar cell areas with each solar cell area having a solar pixel can beformed. The solar pixel can be determined by a diffusion length of aminority current carrier. A plurality of switches can then be formedwith each switch independently controlling one of the plurality of solarcell areas. Electric output of the controlled solar cell area can thenbe monitored and/or displayed.

Additional objects and advantages of the invention will be set forth inpart in the description which follows, and in part will be obvious fromthe description, or may be learned by practice of the invention. Theobjects and advantages of the invention will be realized and attained bymeans of the elements and combinations particularly pointed out in theappended claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several embodiments of theinvention and together with the description, serve to explain theprinciples of the invention.

FIG. 1A depicts an exemplary integrated solar cell device in accordancewith the present teachings.

FIG. 1B depicts a second exemplary integrated solar cell device inaccordance with the present teachings.

FIG. 1C depicts a cross section of the exemplary solar cell devices ofFIGS. 1A-1B in accordance with the present teachings.

FIG. 2 depicts an additional exemplary solar cell device in accordancewith the present teachings.

FIG. 3 depicts an exemplary solar sensor in accordance with the presentteachings.

FIG. 4 depicts a cross-section of an exemplary solar sensor portion inthe direction A-A′ of the device shown in FIG. 3 using the exemplaryintegrations of FIGS. 1A-1C in accordance with the present teachings.

FIG. 5 represents an exemplary solar cell device in accordance with thepresent teachings.

FIGS. 6A-6B depict exemplary super connection systems for solar cellelements in accordance with the present teachings.

FIGS. 7A-7C depict various connection systems for an exemplary solarcell panel in accordance with the present teachings.

FIGS. 8A-8C depict various connection systems for by-passingunderperforming solar cells in accordance with the present teachings.

It should be noted that some details of the FIGS. have been simplifiedand are drawn to facilitate understanding of the inventive embodimentsrather than to maintain strict structural accuracy, detail, and scale.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the exemplary embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts. In thefollowing description, reference is made to the accompanying drawingsthat form a part thereof, and in which is shown by way of illustrationspecific exemplary embodiments in which the invention may be practiced.These embodiments are described in sufficient detail to enable thoseskilled in the art to practice the invention and it is to be understoodthat other embodiments may be utilized and that changes may be madewithout departing from the scope of the invention. The followingdescription is, therefore, merely exemplary.

Exemplary embodiments provide a solar cell device, and method forforming the solar cell device by integrating a switch component into asolar cell element. Exemplary embodiments also provide a solar sensorand methods for forming and using the solar sensor to detect a defectedor a shaded solar cell area. Exemplary embodiments also provide aconnection system of the solar cell elements and method forsuper-connecting solar cell elements so as to provide a desiredconnection path or a desired power output. Exemplary embodiments furtherprovide a system and a method for by-passing underperforming solar cellsof a solar cell component.

As used herein, the term “solar cell element” can include a single solarcell, a solar cell array such as a group or a series of solar cells, ora solar cell panel (or solar cell module) such as a group of solar cellarrays. The solar cell element can have at least two solar cellterminals. In various embodiments, the disclosed “solar cell element” aswell as the related devices, systems and methods can further be extendedto include, for example, a battery or a capacitor.

The switch component can include one or more switches that are eitherintegrated into the solar cell terminal itself or added separately fromthe solar cell as discrete elements. In various embodiments, switchesthat are integrated into either or both of the solar cell terminals caninclude MOS-based structures including, but not limited to, VDMOS(vertically diffused metal oxide semiconductor) or LDMOS (laterallydiffused metal oxide semiconductor) transistors that can utilize thecorresponding solar cell terminal as, for example, the drain of theDMOS-based structure. Such DMOS elements can include both N-type andP-type DMOS (NDMOS and/or PDMOS) depending on the polarity of the solarcell terminal. In various embodiments for integrated switches, a DMOSconfiguration can be preferred as it allows for a low on-stateresistance (Rdson) without reducing the output of the solar cellelement. While a bipolar transistor switch, including both vertical andlateral PNP and NPN transistors, can also be integrated into one or bothterminals of the solar cell element, these are not preferred for theintegration due to their high voltage drop even when operated in theirsaturation regions.

For embodiments that include discrete switches that are not integratedinto the solar cell terminals, there are a variety of switches that canbe used including, but not limited to, any MOS (metal oxidesemiconductor) transistor including PMOS, NMOS, LDMOS, and VDMOS; anybipolar transistor including NPN, PNP or IGBJT (insulated gate bipolartransistor); any FET (field effect transistor) including PFET or NFET;or any mechanically operated switches including configurations that useconventional mechanically actuated or electrically actuated (such asrelays) switches in SPST (single pole single throw), SPDT (single poledouble throw), as well as SPMT (single pole multiple throw)configurations for integrations that connect to a single or bothterminals of the solar cell element, or switches in DPST (double polesingle throw), DPDT (double pole double throw), as well as DPMT (doublepole multiple throw) configurations that connect to both terminals ofthe solar cell element.

In various embodiments, the MOS-based switches can be integrated withone or both terminals of the solar cell element. The integrated solarcell terminal(s) can be combined with one of a source region and a drainregion of the MOS-based switch component to have a common contact forthe disclosed solar cell device. In some embodiments, the integrated orcombined solar cell terminal can still keep its contact, which is alsoreferred to herein as an “external contact”, in order to provide moreconnection flexibilities.

As disclosed herein, the term “external contact” refers to an electricalcontact to the solar cell terminal, for example, to bypass a switchcomponent so as to allow a separate electrical connection to theaffected terminal of the solar cell element.

In various embodiments, when a plurality of MOS-based switches are usedfor the switch component, the MOS-based switches can be formed to have acommon drain region or a common source region according to theintegration design of the solar cell device.

FIGS. 1A-1C depict an exemplary solar cell device having a MOS-basedswitch component integrated within a single solar cell in accordancewith the present teachings. Specifically, FIG. 1C depicts schematiccross section of an exemplary solar cell device 100C according to FIGS.1A-1B in accordance with the present teachings.

It should be readily apparent to one of ordinary skill in the art thatthe devices depicted in FIGS. 1A-1C represent generalized schematicillustrations and that other components can be added or existingcomponents can be removed or modified. In addition, although a singlesolar cell is depicted for the solar cell element in FIGS. 1A-1C, one ofordinary skill in the art would understand that other solar cellelements including, but not limited to, a solar cell array, or a solarcell panel, can be used for the disclosed solar cell device. Further,any solar cell elements that are compatible with the materials andfabrication of MOS technologies can be used for the disclosed solar celldevice 110 in FIGS. 1A-1C.

It is also possible that the solar cell element 110 in FIGS. 1A-1B canrepresent a conventional battery or even a high value capacitor. Suchconfigurations can allow for cell balancing applications in batterypacks, for example, or other sources of power that include multipleconnected batteries or capacitors.

For simplicity, FIGS. 1A-1C show an exemplary integration of oneMOS-based structure 120 with an exemplary single solar cell 110. Asshown, the solar cell 110 can have two terminals or two contactdiffusion regions 112 and 114. The MOS-based structure 120 can have, forexample, a drain region 123, a source region 129 and a gate 126.

The MOS-based structure 120 can be used as a switch using the gate 126to control, e.g., to turn on and off, the solar cell 110, so as tocontrol power output, e.g., current and/or voltage, of the solar cell110. In an exemplary embodiment, the MOS-based structure 120, such as aVDMOS, can only need a breakdown voltage of a few volts and can bedesignated with a low on-state resistance (Rdson).

In the illustrated examples, the MOS-based structure 120 can beintegrated with the exemplary terminal 114 of the solar cell 110. Forexample, the drain region 123 of the MOS-based structure 120 can beintegrated or combined with the terminal 114 of the solar cell 110. Theintegrated solar cell terminal 114 may keep its own external contact(see 114 c) as shown in FIGS. 1A and 1C, or alternatively, the externalcontact 114 c may be removed using the common contact with the drainregion 123 of the MOS-based structure 120, as shown in FIG. 1B.

As shown in FIG. 1C, an exemplary DMOS switch 120 can be integrated intoone of the terminals of a conventional solar cell, i.e., the n terminal114, in order to switch the solar cell on and off. One example of theconventional solar cells can include silicon-based photovoltaic cellshaving a solar cell array or a solar cell panel including alternating pand n contact diffusions. In the illustrated embodiment of FIG. 1C, then terminal of the solar cell can be integrated by the exemplaryDMOS-based structure, although one of ordinary skill in the art wouldunderstand that any other MOS-based switches can be used for thedisclosed solar cell device.

The device 100C can thus include a solar cell p terminal 112, a solarcell n terminal 114, and a DMOS-based structure 120 formed in asemiconductor substrate 130.

The DMOS-based structure 120 can be, for example, a vertical DMOS-basedstructure that includes source regions (n+) 127 in p-body regions125,122, p-body contact regions 124 (e.g., a heavily doped region p+), adrain region 123, a gate 126, and insulative regions 105 as known by oneof ordinary skill in the art.

The integrated solar cell n terminal 114, e.g., the heavily doped (n+)region 114, can also be used as a drain region contact of the DMOS-basedstructure 120. The p-body 122 and 125 can be formed on top of the drainregion 123, which can be a deep n well formed by implantation and/ordiffusion process in a p-type layer in a typical silicon substrate (alsosee 130), for example. The source region 127 and p-body region 122 canbe shorted together by the combination of a p-body contact region 124and the p-body-source contact metallization 129 c.

In various embodiments, the electrical contacts, such as, for example,the solar cell p-contact 112 c, the solar cell n-contact 114 c, and thecontacts 129 c, 114 c and 126 for the source region, the drain regionand the gate, can include the use of copper interconnect and othermetals that are compatible with solar cell and semiconductor processing.In various embodiments, the gate material can further include, e.g.,polysilicon that is ion implanted or in-situ doped to be N+ or P+ inpolarity.

In some embodiments, the solar cell n terminal contact 114 c can be usedas an external contact for the solar cell device 110C (also see FIG.1A). In other embodiments, the cell n terminal contact 114 c can beremoved (not shown) from FIG. 1C, as also indicated in FIG. 1B.

In various embodiments, the conductivity of semiconductor regions, i.e.,the use of p and n type semiconductor regions, can be reversed for thesolar cell devices 100C along with any other devices disclosed herein.

In various embodiments, a plurality of switches can be included for theswitch component in the disclosed solar cell device. For example, FIG. 2depicts another exemplary solar cell device in accordance with thepresent teachings. It should be readily apparent to one of ordinaryskill in the art that the device 200 depicted in FIG. 2 represents ageneralized schematic illustration and that other components/devices canbe added or existing components/devices can be removed or modified.

As shown in FIG. 2, the exemplary solar cell device 200 can include asolar cell 110 having two terminals (or contact diffusions) 112 and 114.The device 200 can also include a number of MOS-based switches 120 a-cintegrated with one of the solar cell terminals, e.g., the terminal 114.In various embodiments, as similarly described in FIGS. 1A-1C, theterminal 114 may or may not exist but sharing a common contact with thedrain region 123 of the MOS-based switch component 120.

In the specific embodiment of FIG. 2, while three MOS-based structures120 are integrated with the solar cell 110 sharing a common drain region123 for the solar cell device 200, one of ordinary skill in the art willunderstand that any number of switch structures can be integrated withinthe solar cell. In addition, the formation structure of the device 200can be similar to that shown in FIG. 1C, except that more switches(e.g., two more as for the device 200) can be formed in series withinthe solar cell device sharing a common drain region. In variousembodiments, the multiplicity of switches for the disclosed solar celldevice can provide a variety of connection flexibilities with any othercomponents that are related to the solar cell.

Various embodiments can thus include a method for forming a solar celldevice. For example, a semiconductor solar cell element that includes ap contact diffusion region and an n contact diffusion region can firstbe provided or formed in a semiconductor substrate. A MOS-basedstructure can then be integrated with at least one of the n contactdiffusion region and the p contact diffusion region in the semiconductorsubstrate so as to control the semiconductor solar cell element as aswitch. In various embodiments, a plurality of MOS-based structures canbe formed in the semiconductor substrate having a common drain region ora common source region.

In various embodiments, the integrated plurality of MOS-based structurescan have a breakdown voltage consistent with the number of solar cellsin the stack. For example, a single solar cell switch can operate with abreakdown voltage of about 1 or 2 volts, while solar cell stacks canrequire a breakdown voltage of about 10 volts.

Various embodiments can also include a solar sensor and its formation inaccordance with the present teachings. For example, FIG. 3 depicts aportion of an exemplary solar sensor component 300 in accordance withvarious embodiments of the present teachings. It should be readilyapparent to one of ordinary skill in the art that the sensor 300depicted in FIG. 3 represents a generalized schematic illustration andthat other components/devices can be added or existingcomponents/devices can be removed or modified.

As shown, the solar sensor component 300 can include a plurality ofsolar cell areas 310, and a plurality of switch components 320. Thesolar sensor component 300 can include various sensor elements with eachsensor elements (e.g., 300 a or 300 b) including one solar cell area(e.g., 310 a or 310 b) and one switch component (e.g., 320 a or 320 b)associated therewith.

Each solar cell area 310 can be defined by, e.g., a single pixel in thearray having a pixel size P and divided from the solar sensor component300. The pixel size P can depend on a diffusion length of holes and/orelectrons drifting in the semiconductor. For example, in siliconphotovoltaic cells, when solar radiation falls on a silicon n-pjunction, photons with wavelength less than 1.13 μm can generateelectron-hole pairs. The electric field in the depletion layer can drivethe electrons to the n-type side and the holes to the p-type side. Thiscan separate most of the electrons and holes before they can recombine.The “diffusion length” can be determined by how far the minority currentcarriers, electrons or holes, can drift or diffuse in the area beforetheir recombination or before reaching the junction. Each solar cellarea 310 can therefore include at least one single solar pixel.

Each switch component 320 can independently address the associated solarcell area 310. In various embodiments, each switch component 320 can beintegrated within one of the solar cell areas 310 or can be discretefrom the corresponding solar cell area 310.

Note that, although the solar sensor component shown in FIG. 3 includes36 solar sensor elements or solar sensor areas in a 6×6 array, one ofordinary skill in the art would understand that any other numbers ofsolar sensor elements or any other suitable arrangements/arrays of thesolar sensor elements/areas can be used for the disclosed solar sensorcomponent 300.

FIG. 4 depicts a cross-section portion of an exemplary solar sensor 400using the integration shown in FIG. 1C in accordance with the presentteachings. The cross-section of FIG. 4 shows a solar sensor portion inthe direction of A-A′ of FIG. 3, wherein the portion can include sensorelements 300 a-b.

In various embodiments, the integration of FIG. 1 can be used as anexample for each sensor element. As shown, the device 100C shown in FIG.1C can be used as an element 300 a or 300 b for the solar sensor 400,wherein each switch component independently control the associated orcorresponding solar cell.

In various embodiments, the solar sensor 300 and/or 400 can furtherinclude a readout component used to display an electric output from eachindividual solar cell area controlled by the corresponding independentswitch component. Typically, for a solar cell, an electrical loadresistance R can be connected across the semiconductor junction. Theelectrons and holes can produce a current, and the energy in the solarradiation can then be converted into electrical energy in the circuit.

When one solar cell area of the solar cell sensor has defects,impurities or is shaded, the diffusion length and the life time of thecurrent carriers, i.e., the holes or the electrons, can be reduced.Electronic power output may not be measured for this individual solarcell area. Defects or shade can then be detected. In one embodiment, thesolar sensor 300 or 400 can be used for sensing light dark areas. Forexample, shade or photon irradiation detection can be performed bylocally collecting the electric outputs.

Various embodiments can further include a method for forming solarsensors, for example, using the method described in FIGS. 1A-1C and 2.In another example, the method can include first forming or providing asolar cell component having a plurality of solar cell areas. Each solarcell area can be defined by a pixel of a diffusion length of theelectrons or holes. A plurality of switches can then be formed orprovided with each switch independently controlling one solar cell area.In order to determine a defected solar cell area or a shaded area, theelectric output of each solar cell area can be monitored.

In various embodiments, super connection schemes, systems and methodscan be provided for solar cell based applications. The super connectioncan provide a variety of arrangements and connection paths for solarcell elements with a desired electric output.

For simplicity of illustration, FIG. 5 represents an exemplary symbolfor the solar cell devices in accordance with the present teachings. Asshown, the solar cell device 500 can include a solar cell element 510having two terminals 512 and 514. The solar cell element 510 can be,e.g., a single solar cell as shown in FIGS. 1A-1C and FIG. 2; a group ofsolar cells, such as a solar cell array; and/or a solar cell panel, suchas a group of solar cell arrays.

The solar cell device 500 can also include a switch component 520 havingone or more switches 520 a-c associated with one of the solar cellterminals, e.g., 514. In various embodiments, the switch component 520can be an integrated switch component, e.g., formed within a solar cellelement as shown in FIG. 1C and FIG. 4; or a discrete switch componentfrom the solar cell element 510. Any suitable switch as disclosed hereinor as known to one of ordinary skill in the art can be used for thediscrete switch component.

Although three switches are depicted in FIG. 5 for the switch component520, various embodiments can include a number of switches that is morethan or less than three for the switch component 520.

FIGS. 6-8 provide various embodiments of connection systems andconnection methods of solar cell elements. In various embodiments, theterm “super connection” refers to a connection scheme that provides allpossible cross connections between any adjacent solar cell elements. Thesuper connection can be fulfilled by associating switch components witheach solar cell element, wherein each switch component can furtherinclude various numbers of switches. Such super connection can provideflexibility to wire, e.g., an array or a panel of the solar cellelements, and therefore provide flexibility on power outputs. In anexemplary embodiment, a number of solar cell elements can be superconnected in a manner of series-parallel management. That is, one ormore series of solar cell elements can be super connected in parallel.

FIGS. 6A-6B depict exemplary super connection systems in accordance withthe present teachings. It should be readily apparent to one of ordinaryskill in the art that the systems depicted in FIGS. 6A-6B representgeneralized schematic illustrations and that other components/devicescan be added or existing components/devices can be removed or modified.

In various embodiments, elements, components and devices related to thesolar cell device 500 shown in FIG. 5 can be used as examples for thesuper connections of solar cell elements.

In FIG. 6A, the connection system 600A can include a plurality of solarcell elements 610 a-f with each solar cell element associated with oneor more adjacent switches 620 a-f from a plurality of switch componentsto form the super connection. In various embodiments, switches connectedto a specific solar cell element can be from different switch componentsand each switch component can include at least one switch. Solar cellelements can therefore be super interconnected through a variety ofconnections using, e.g., the associated switches 620, and/or externalcontacts 612 a-f or 614 a-f. Having the super connected system, each ofthe associated switches can be set to support a desired connectionarrangement of the plurality of solar cell elements for a controlledpower output.

In FIG. 6A, for example, the solar cell element 610 b can be superconnected using an exemplary series-parallel connection scheme. Asshown, the solar cell element 610 b can be connected to a first adjacentsolar cell element 610 a through the external contact 612 b and theswitch 620 a 1; the solar cell element 610 b can also be connected to asecond adjacent solar cell element 610 c through the switch 620 b 1 andan external contact 612 c; the solar cell element 610 b can further beconnected to a third adjacent solar cell element 610 e through theexternal contact 612 b and the switch 620 e 2, and/or through the switch620 b 2 and the external contact 612 e; and, the solar cell element 610b can even further be connected to a forth or fifth adjacent solar cellelement 610 d or 610 f through, for example, the crossing wire 634/635or the cross wire 632/633 along with related switches.

In various embodiments, when more solar cell elements are needed to beconnected with the exemplary solar cell element 610 b, more switches 620b, more external contacts such as 614 b and/or more crossing wires canbe available as desired. Likewise, other solar cell elements, e.g., 610a, and 610 c-f, in FIG. 6A can go through such super connection process.

In various embodiments, the super connection of FIG. 6A can besimplified or cleaned by removing one or more redundant switchcomponent(s) or crossing wire(s) using some common nodes instead. Forexample, the switch components 620 c, 620 e and 620 f as well as thecrossing wires 631 and 633 can be “effectively removed” from theconnection system 600A leaving a “simplified” super connection system600B shown in FIG. 6B.

As used herein, the “effectively removed” switches and crossing wiresmay physically exist, i.e., not necessarily to be physically removed,but may be electrically switched off with no current flowingthere-through. For example, switches can be “effectively removed” by anelectrical by-passing, e.g., using external contacts; and crossing wirescan be “effectively removed” by suitable switch settings with no currentallowed to flow through.

As shown in FIG. 6B, the connection system 600B can include a pluralityof solar cell elements 610 a-f with at least one solar cell elementassociated with one or more adjacent switches 620 a-f from a pluralityof switch components to form the super connection.

In various embodiments, each switch that is associated with the solarcell elements can be set to support a desired connection arrangement ofthe plurality of solar cell elements for a controlled power output. Thatis, by controlling the switches, any desired configurations and outputscan be obtained.

FIGS. 7A-7C depict various connection systems for an exemplary panelhaving 6 solar cell elements in accordance with the present teachings.As shown, the connection systems use a box 705 to show one solar celldevice (e.g., the device 500 shown in FIG. 5) including a solar cellelement and the associated switches. It should be readily apparent toone of ordinary skill in the art that the systems depicted in FIGS.7A-7C represent generalized schematic illustrations and that othercomponents/devices/boxes can be added or existingcomponents/devices/boxes can be removed or modified.

In various embodiments, the connection systems shown in FIGS. 7A-7C canbe obtained by first super connecting the exemplary 6 solar cellelements, for example, as shown in FIG. 6A or 6B, and then setting eachswitch associated with the solar cell elements to form variousconnection arrangements as needed.

In one embodiment when series-parallel management is used for theexemplary 6 solar cell panel, possible connection arrangements caninclude, for example, a 1×6 arrangement (see FIG. 7A), a 2×3 arrangement(see FIG. 7B), a 3×2 arrangement (see FIG. 7C), and/or a 6×1 arrangement(not shown). In this case, each switch component can have two switchesfor the solar cell panel that has 6 solar cell elements.

In FIG. 7A, the 1×6 connection arrangement can have 1 loop (see 700 a)of 6 solar cell elements (see boxes 705) connected in series providingtwo connection contacts 700 a 1 and 700 a 2 for the panel.

In FIG. 7B, the 2×3 connection arrangement can have 2 parallel loops(see 700 b) of 3 solar cell elements (see boxes 705) connected in seriesproviding four connection contacts 700 b 1-700 b 4 for the panel.

In FIG. 7C, the 3×2 connection arrangement can have 3 parallel loops(see 700 c) of 2 solar cell elements (see boxes 705) connected in seriesproviding six connection contacts 700 c 1-700 c 6 for the panel.

Such connection arrangements 700 a-c can be obtained from switching thesuper connected solar cell system as shown in FIG. 6A or 6B. Forexample, in order to have a connection arrangement of 1×6 of FIG. 7A,switches of the super connected system 600A (see FIG. 6A) including, forexample, 620 a 1, 620 b 1, 620 c 1, 620 d 1, 620 e 1 can be turned on,while switches of 620 a 2, 620 b 2, 620 c 2, 620 d 2, 620 e 2, 620 f 1and 620 f 2 can be turned off. In addition, crossing wires 631, 632,633, 634 and 635 (see FIG. 6A) can be effectively removed because thereis no current path due to the switch settings, while crossing wire 636stay connected because corresponding switch settings allow current flow.Although the crossing wires 631, 632, 633, 634 and 635 are notillustrated in FIG. 7A, these “effectively removed” crossing wires mayphysically exist but be electrically switched off. Further, in variousembodiments, some of the switches (e.g., switches 620 c 1 as well as theswitch 620 c 2) can be bypassed by using external contacts (e.g.,contact 614 c) for this illustrated connection arrangement.

In various embodiments, the connection arrangement of FIG. 7A can beobtained by setting switches from the simplified super connection systemof FIG. 6B.

Likewise, the connection systems shown in FIG. 7B and FIG. 7C can alsobe obtained by setting related switches from the super connection systemof FIGS. 6A-6B, as similarly described for the arrangement process ofFIG. 7A. In addition, some of the crossing wires may be “effectivelyremoved” from the super connection system shown in FIGS. 6A-6B usingswitch settings, which are not necessarily physically removed. Forexample, for the connection system 700 b, all the crossing wires 631-636can be “effectively removed”, while for the connection system 700 c,crossing wires 631, 633, and 635 can be “effectively removed”.

In this manner, by choosing suitable switches or by re-switchingsuitable switches of the disclosed super connection system, theconnections of the solar cell elements can be rearranged. In variousembodiments, the solar cell panel can have various number of solar cellelements connected as desired from a related super connection systemusing the exemplary systems and methods shown in FIGS. 6-7.

For example, the solar cell panel can also have 12 solar cell elementsthat need to be connected. For a desired electric output and thus adesired solar cell connection, the 12 solar cell elements can be superconnected with each solar cell element interconnected with all adjacentsolar cell elements by switches, external contacts and/or crossing wiresusing similar methods described in FIGS. 6-7.

As a result, various configurations can be obtained for the 12 solarcell elements including: (1) a 1×12 connection arrangement having 1 loopof 12 solar cell elements connected in series providing two connectioncontacts for the panel; (2) a 2×6 connection arrangement having 2parallel loops of 6 solar cell elements connected in series providingfour connection contacts for the panel; (3) a 3×4 connection arrangementhaving 3 parallel loops of 4 solar cell elements connected in seriesproviding four connection contacts for the panel; (4) a 4×3 connectionarrangement having 4 parallel loops of 3 solar cell elements connectedin series providing eight connection contacts for the panel; (5) a 6×2connection arrangement having 6 parallel loops of 2 solar cell elementsconnected in series providing ten connection contacts or more for thepanel; and/or (6) a 12×1 connection arrangement having 12 individualsolar cell elements for the panel.

In various embodiments, the super connection system disclosed herein canbe used to bypass one or more underperforming solar cell elements (e.g.,that are at least partially shaded, or defective) from groups of solarcell elements. Thus, if a single solar cell element fails, there can bealternate paths by which the output power of all other solar cellelements/devices can contribute to the total output power of the solarcell array or panel. In various embodiments, after by-passing theunderperforming solar cell elements, e.g., using switches, all of theother remaining solar cell elements can be arranged or re-arrangedaccording to the disclosed super connection process.

Still using the super connection system 600A as an example, FIGS. 8A-8Cshow various by-passing connection systems in accordance with thepresent teachings. It should be readily apparent to one of ordinaryskill in the art that the systems depicted in FIGS. 8A-8C representgeneralized schematic illustrations and that other components/devicescan be added or existing components/devices can be removed or modified.

In various embodiments, underperforming solar cell(s) of a plurality ofsolar cell elements can first be disconnected, e.g., by turning offassociated switches, while other solar cell elements of the plurality ofsolar cell elements can remain connected or can be reconnected orrearranged to provide a second suitable super connection. In variousembodiments, the rearranged other solar cell elements can include one ormore loops of solar cell series according to a power output.

In one exemplary embodiment shown in FIG. 8A, when one solar cell device805 e underperforms, the solar cell device 805 e, including the relatedsolar cell element (also see the solar cell element 610 e of FIG. 6A)and/or its related switches, can be disconnected, e.g., by turning offall associated switches, from the plurality of solar cell devices.Remaining solar cell devices (see 610 a-d and 610 f) can then bere-arranged or re-super connected, e.g., connected in series (see 800a), whereby providing connection contacts of 800 a 1 and 800 a 2.

Likewise, in another exemplary embodiment shown in FIG. 8B, when anothersolar cell device 805 f (also see the solar cell element 610 f of FIG.6A) underperforms and is disconnected from the plurality of solar celldevices, the other remaining solar cell devices (see 610 a-e) can bere-arranged or re-super connected in one series (see 800 b), wherebyproviding connection contacts of 800 b 1 and 800 b 2.

In an additional exemplary embodiment shown in FIG. 8C, when the solarcell device 805 f underperforms and is disconnected, the other remainingsolar cell devices (see 610 a-e) can be re-arranged or re-superconnected to have two loops 800 c of connected solar cell series (see600 a-c and 600 d-e) providing connection contacts of 800 c 1, 800 c 2,800 c 3 and 800 c 4.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains certainerrors necessarily resulting from the standard deviation found in theirrespective testing measurements. Moreover, all ranges disclosed hereinare to be understood to encompass any and all sub-ranges subsumedtherein. For example, a range of “less than 10” can include any and allsub-ranges between (and including) the minimum value of zero and themaximum value of 10, that is, any and all sub-ranges having a minimumvalue of equal to or greater than zero and a maximum value of equal toor less than 10, e.g., 1 to 5. In certain cases, the numerical values asstated for the parameter can take on negative values. In this case, theexample value of range stated as “less than 10” can assume values asdefined earlier plus negative values, e.g. −1, −1.2, −1.89, −2, −2.5,−3, −10, −20, −30, etc.

While the invention has been illustrated with respect to one or moreimplementations, alterations and/or modifications can be made to theillustrated examples without departing from the spirit and scope of theappended claims. In addition, while a particular feature of theinvention may have been disclosed with respect to only one of severalimplementations, such feature may be combined with one or more otherfeatures of the other implementations as may be desired and advantageousfor any given or particular function. Furthermore, to the extent thatthe terms “including”, “includes”, “having”, “has”, “with”, or variantsthereof are used in either the detailed description and the claims, suchterms are intended to be inclusive in a manner similar to the term“comprising.” As used herein, the term “one or more of” with respect toa listing of items such as, for example, A and B, means A alone, Balone, or A and B. The term “at least one of” is used to mean one ormore of the listed items can be selected.

Other embodiments of the invention will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

What is claimed is:
 1. A method of operation of a solar cell element,comprising: monitoring an electrical output of a solar cell area in thesolar cell element; determining if the electrical output is less than apredetermined value; and bypassing the solar cell area in the solar cellelement if the electrical output is less than the predetermined value.2. The method of claim 1, wherein the bypassing comprises controlling aswitch component in the solar cell area.
 3. The method of claim 1,wherein the bypassing comprises bypassing the electrical output of thesolar cell area in the solar cell element.
 4. The method of claim 1,wherein the monitoring comprises reading the electrical output of thesolar cell area in at least one of a solar cell array and a solar cellpanel.
 5. The method of claim 1, wherein the bypassing comprisescontrolling a switch component integrated together with the solar cellelement, and thereby bypassing the solar cell area.
 6. The method ofclaim 1, wherein the bypassing comprises controlling a source region ora drain region of a semiconductor switch integrated together with asolar cell terminal of the solar cell element.
 7. The method of claim 1,wherein the monitoring comprises reading an electrical signal outputacross two solar cell terminals of the solar cell element, and thebypassing comprises controlling a source region or a drain region of aMOS-based switch, the source region or the drain region of the MOS-basedswitch integrated together with one solar cell terminal of the two solarcell terminals.
 8. A method of operation of a solar cell element,comprising: monitoring an electrical signal output from a solar cellarea in a solar cell element including a p-n junction and a plurality ofsolar cell terminals; determining if the electrical signal output fromthe solar cell area is less than a value; and controlling a switchcomponent integrated together with the solar cell element to bypass thesolar cell area if the electrical signal output from the solar cell areais less than the value, wherein the switch component comprises at leastone source region and drain region of a transistor switch integratedtogether with the solar cell element within a junction isolated region,and the drain region shares one of a p-type doped region or an n-typedoped region of the p-n junction.
 9. The method of claim 8, wherein themonitoring comprises measuring the electrical signal output across twosolar cell terminals of the plurality of solar cell terminals.
 10. Themethod of claim 8, wherein the controlling comprises controlling asource region or drain region of a laterally diffused MOS (LDMOS)transistor or a vertically diffused MOS (VDMOS) transistor.